How to grow fennel

Traditionally grown apart from other crops. Its flowers are still excellent for beneficial insects.

Spacing1 per square foot
Plant outaround your last spring frost
Days to harvest60–90
FrostTakes light frost
HowSow directly in the garden
Family Herbs

Rotation and family

Fennel belongs to the herbs (Lamiaceae / Apiaceae). Small footprint; many attract pollinators and predatory insects.

It can fill gaps in any bed of your rotation.

Plan fennel in your garden

When to plant fennel by zone

ZoneSow / plant out
3May 20 – Jun 10
4May 12 – Jun 2
5Apr 30 – May 21
6Apr 20 – May 11
7Apr 8 – Apr 29
8Mar 26 – Apr 16
9Feb 22 – Mar 15
10Feb 1 – Feb 22

Based on typical frost dates for each zone; b half-zones run about a week earlier in spring. Zones 11–13 are frost-free in most years.

Fennel questions

When should I plant fennel?

Plant fennel outdoors around your last spring frost.

How far apart should I plant fennel?

About 12 inches apart, or 1 per square foot in a square foot garden.

What grows well with fennel?

Traditional companions include marigold. Keep it away from bush bean, cilantro, dill, eggplant, pepper, tomato.

How long does fennel take to grow?

Typically 60–90 days from sowing to first harvest, depending on variety and weather.